The present invention relates to manually manipulable devices for electrically interfacing between an electro-surgical signal generator and an exposed surgical electrode. More particularly, this invention relates to surgical instruments which can be used substantially in the same manner as passive manual instruments but which include switching apparatus for permitting selection and activation of particular electro-surgical functions in association with the instrument. The present invention is especially useful by surgeons in performing electro-surgical procedures.
A wide variety of devices have been developed in the past for use by surgeons in operations. The early developments of hand tools have been supplemented by a further variety of electro-surgical apparatus. For instance, electrical pulses have been used for cauterizing and the like. Further, apparatus using high frequency or RF pulses have been employed for tissue cutting using exposed electrode elements in various configurations such as looped wires, needles, ball tips, blade-like arrangements and the like. The earlier electro-surgical devices generally required actuation via foot switches or manual switches which were inconveniently located for the surgeon or even required handling by an assistant. Such devices tend to degrade the direct control of the surgeon and thus have not always provided satisfactory results.
Accordingly, devices have been developed for the purpose of providing apparatus usable somewhat like passive surgical tool instruments but which incorporate immediately available switch apparatus so that the surgeon can directly select the electro-surgical procedure required while the instrument is in place. Devices for this purpose employing a cylindrical handle and rocker switch arrangement are shown in U.S. Pat. No. 3,801,766 by Morrison and U.S. Pat. No. 3,648,001 by Anderson, et al. However, there has been a continuing need for a surgical instrument which is adaptable for usage as a passive tool including means for selectable actuation as an electro-surgical device which has the feel of previous passive surgical instruments. Further, there has been a continuing need for such a device which can be totally sealed from the environment so that elements or materials associated with performance of a surgical procedure will not enter the instrument. Migration into the instrument by fluids associated with the operation can not only discount the effects of sterilization but can even cause malfunctioning or inadvertent functioning of the switch elements particularly if the fluid is an electrical conductor, such as blood. Still further, there has been a continuing need for such a combined passive and electro-surgical instrument which permits selection from amongst a plurality of switch functions by the surgeon without visual distraction from the procedure being performed.